I OT'd praetorium for the first time in ages. Right before the ultima weapon echo, I cast cure a couple of times after the MT had been spamming 3 or 4 halone combos to try and build enmity. Curing myself twice while full HP in sword oath nearly stole the hate from him. He had slightly better gear with a slightly worse weapon, so it's not like I was stealing enmity from a fresh 50 or whatever.

I'll see what sort of effect flash has if I'm ever in that situation again, but I'm almost certain it's not as powerful. I kind of wonder if Ultima's got some kind of enmity multiplier for heals or something.